I have a small ceramic bowl in my set to represent a need. If the bowl is open side up it indicates that something is needed. If it is with another piece, the other piece tells what is needed. If it is isolated it could indicate a need that hasn’t been articulated yet. We know something is missing, but we haven’t been able to pin down exactly what it is. It could just be a vague uneasiness that we shrug off, or it could be something that is taking up a lot of real estate in our mind that we are actively trying to pin down so that we can do something about. If the bowl presents bottom up it is silent. That doesn’t mean that we don’t need anything – we all need various things all of the time. It just says that this reading has nothing to say on the matter.
I got my bowl from a piece of doll house furniture I bought in the dollar store. It was glued to a shelf and I pried it up and cleaned the glue off of the bottom. You can get one inexpensively from a toy store, or from eBay. Some even come with miniature items of food in them, though I would want one with removable food so that the idea of “my bowl is empty” is clear. You don’t have to use a bowl – a basket or any miniature container would work the same way. You could also use a piece that is not a container at all if you have something else that represents need to you, or you could use something abstract just because you like it.
This is not what I would call a “must have” piece. It is more in the category of “nice to have.” However, I find it quite useful. Give it a try if you think it might be useful in your set.